With Mobile number portability to start today, here’s how you can shift from your current service provider to a new one.
Send an SMS from your phone to 1900. Your present company will reply with a unique porting code. Use that code while filling out a detailed form for the company you want to shift to. Within 48 hours, that company will take over all your cell services. The fee charge may cost you about Rs 19.
Your cell number will be switched off for only one hour. All bills after that are paid to your new company. You’ll be stuck with them for at least 50 days before you can shift again, so choose with care. While you can shift from a GSM service to CDMA or vice versa, you cannot shift from one state to another.
Update:- More on Mobile Number Portability here